Why You Need to Get More Sleep

A bad night’s sleep can make you feel grumpy, groggy, and exhausted. But for people with diabetes, missing sleep may be more serious.

Studies have shown that, in people with diabetes, overnight restlessness or substandard sleep can lead to higher glucose levels the next day. For the general population, poor sleep can lead to insulin resistance and a greater risk for type 2 diabetes. It’s clear that the quality of one’s slumber plays a major role in blood glucose levels.

Common Complaints

Sleep problems are more prevalent in people with diabetes, says Timothy Morgenthaler, MD, immediate past president of the American Academy of Sleep Medicine and professor of medicine at the Mayo Clinic in Rochester, Minnesota. People may get up to urinate multiple times due to high blood glucose or be awakened by symptoms of a low. Nighttime blood glucose checks are also disruptive.

What’s more, two in three people with type 2 diabetes have obstructive sleep apnea, the most common type of sleep disorder, says Eve Van Cauter, PhD, Frederick H. Rawson professor of medicine and director of the Sleep Metabolism and Health Center at the University of Chicago. Sleep apnea is a condition in which people intermittently stop and start breathing while they’re asleep.

Stress Signals

Here’s what happens to your body when you’re shorton shut-eye:

Brain Fog: “Your brain is a glucose guzzler,” says Van Cauter. Outside of mealtimes, the brain consumes almost half of all glucose used by the body. Because the brain does not work efficiently after a poor night’s sleep, it drinks up less glucose. The result: You’ll have more trouble focusing the next day and will have higher blood glucose levels than you typically would after good-quality sleep.

Hormone Shifts: Insufficient sleep, which is often interpreted by the body as a stressful situation, activates the sympathetic nervous system and stress hormones, such as cortisol, Van Cauter says. The heightened hormone activity may be why you feel a higher level of anxiety and stress the day after a restless night. Poor sleep will reduce insulin action, reduce insulin sensitivity, and decrease the release of insulin by the beta cells. So “glucose levels will rise,” Van Cauter says.

Oxygen Gaps: The beta cells in the pancreas are very sensitive to oxygen levels, much more so than liver or muscle cells, says Van Cauter. When a person stops breathing due to sleep apnea, it impacts the beta cells’ ability to produce insulin. The stress this puts on the body can lead to higher blood glucose readings the next day.

Heart Smart

Obstructive sleep apnea can affect more than just glucose control—it can also increase your risk for heart disease. But many people don’t even know they have the disorder. Answer these questions to evaluate the quality of your sleep:

Do you snore?

Are you being treated for high blood pressure?

Are you overweight?

Do you get headaches in the morning?

Do you feel poorly rested?

If you have diabetes, snore, and have high blood pressure, there’s a good chance you have sleep apnea, says Morgenthaler. He suggests asking your doctor about an evaluation. “One of the great things about being a sleep specialist is we have very good capability to diagnose the problem with your sleep,” he says. “And our treatments actually work, particularly with sleep apnea.”

Hunger High

Your ability to make healthful food choices can be compromised when you’re tired. If an apple and a jelly doughnut are put in front of you, your brain might tell you to scarf down the donut. There is a tendency to eat more food, especially high-carbohydrate, high-fat junk food, following a night of insufficient sleep, says Cynthia Fritschi, PhD, RN, CDE, assistant professor in the Department of Behavioral Health Sciences at the University of Illinois at Chicago.

Sleep apnea in particular is known to impact the hormones that regulate appetite, says Morgenthaler. It causes you to feel hungrier and weakens the signal that lets you know you’re full. This can cause weight gain, which could lead to worsening sleep apnea. “It’s a very slippery slope of interaction between obesity, [type 2] diabetes, and sleep apnea,” he says. “You need to address them all at the same time.”

Shift workers are prone to poor sleep, too, says Van Cauter, and at a greater risk for type 2 diabetes. When shift work requires you to be awake during nighttime hours, it can disrupt the body’s circadian rhythm, an internal clock that keeps your body regulated with cues from the outside world, such as light. This can impact your ability to sleep during the day and can stimulate those appetite hormones when it’s bedtime.

Seeking Treatment

If you have diabetes and sleep apnea, treating the sleep apnea can bring about marked improvements to your overall health. Studies have shown that the more severe your sleep apnea, the worse your glycemic control, even after controlling for factors such as age, sex, and body mass index. “If you’re a person with type 2 diabetes and you have obstructive sleep apnea, you are less likely to be able to control your diabetes with the same kind of medication than a person without sleep apnea,” says Van Cauter. So anything you can do to lessen the severity of sleep apnea will help control your diabetes.

In the past, evidence was mixed on whether treating sleep apnea with a continuous positive airway pressure (CPAP) device, which delivers mild continuous air pressure though a breathing mask to keep the airways open, could improve glucose levels. However, several recent studies have found that CPAP treatment does improve glycemic control in people with type 2 diabetes when a person uses it for a full seven hours. These results will be published later this year in the American Journal of Respiratory and Critical Care Medicine. “The studies have suggested that going from severe sleep apnea to mild or no sleep apnea has the potential effect of a 1 percent decrease in hemoglobin A1C,” Van Cauter says. That’s a significant improvement in blood glucose control.

The CPAP device is a bit cumbersome, however, which can be a turnoff. Wendy Waldman, 56, of Birmingham, Alabama, has type 2 diabetes. She says the incessant hum and awkwardness of her CPAP machine kept her from getting a good night’s sleep. “I would sleep for about four hours with it on, and then I’d get up and throw the mask across the room,” she says.

Adjusting to a CPAP machine can be difficult, but there are some ways to smooth the process:

Make sure your mask fits right. If it’s too loose or too tight, it will be uncomfortable.

Use the heated humidified air setting on your CPAP. This can clear up any nasal side effects, such as congestion or runny nose.

To get accustomed to the initial awkwardness, use your CPAP during the day, starting with 10 minutes at a time.

Try using the mask for two hours every night, gradually working your way up to your entire night’s sleep.

Some people may not necessarily need a CPAP machine to see improvements in sleep quality. Losing weight and sleeping on your side may be enough to reduce or eliminate sleep apnea, Van Cauter says.

Some evidence suggests that dental devices worn overnight can effectively treat mild to moderate sleep apnea by moving the lower jaw slightly forward and down to open the airway. But Morgenthaler says CPAP should be considered when treating severe sleep apnea.

Analyze This

Do you feel tired, doze off during the day, or snore? With these signs, your doctor may refer you to a sleep specialist or to an accredited lab to do a sleep study.

Sleep studies go something like this: You’ll snooze at the lab, which may be designed to look like a comfortable hotel room. A sleep technician puts sticky patches with sensors, called electrodes, on your face and body to monitor your brain waves, heart rate, movement, and the amount of oxygen in your blood during sleep. That data can help determine whether you have a sleep disorder.